Background Music Generator for a Podcast App

Problem/Feature Description

A podcast production company wants to add auto-generated background music to their episodes. They've chosen the ElevenLabs Music API for this. They need a Python command-line tool that takes a mood description (e.g. "calm ambient background") and a duration in seconds, then generates an MP3 file.

The tool should be a single Python script called generate_bgm.py that:

• Accepts a mood description and duration from the user (can be hardcoded for now with example values — a 45-second calm ambient track)
• Connects to the ElevenLabs Music API to generate the music
• Saves the resulting audio to an MP3 file
• Includes basic error handling for API failures

The team wants this to be a clean, production-ready script they can integrate into their pipeline.

Output Specification

• generate_bgm.py — The Python script
• requirements.txt — Python dependencies needed